Apparatus for the optimizing of the regulation adjustment of a spinning machine as well as a procedure corresponding thereto

Description

DESCRIPTION

[0001] The invention concerns an apparatus for the optimization of the regulation adjustment of a spinning works machine with, for example, a draw frame, in particular, a regulated draw frame, a carding machine, or a combing machine. Likewise, the invention concerns first a procedure corresponding to a regulation of said machines and second, a machine for a spinning works.

[0002] A spinning works machine with a regulated draw frame can be, for example, the regulated draw frame RS-D 30 of the Firm Rieter, wherein the thickness-variations of the entering fiber bands at the feed end are continually monitored by a mechanical device (groove-roll/feeler roll) and subsequently converted into electrical signals. The measured values are transmitted to an electronic memory with a variable, time delayed response. Achieved by the said time delay is, that the draft between the mid-roll and the delivery roll of the draw frame occurs exactly at that moment when the band piece, which had been measured by a feeler roll pair, finds itself at a point of draft. The time delay then so reacts, that corresponding band pieces can run through the distance between the feeler roll pair and the first location of draft. When the piece of band reaches the hypothetical draft point in the draft field, then a corresponding value is released by the electronic memory. The termination of the distance, which separates, respectively, the feeler roll pair and the point of draft, is called the zero point of regulation. When the zero point is reached, then, conditioned by the value of the measurement, a variable speed motor positioning operation is carried out.

[0003] Especially, in the case of a change of fiber material, or batches thereof in regulated draw frames and generally in the case of all spinning machines and universally where textile working machines are concerned, extensive re-optimization of the machine regulation is necessary. In the case of draw frames, for instance, the mechanical adjustments must be optimized, that is the lengths of the draft fields, the tensioning, the upper roll loadings, the speed of output and the like. At the same time, the process controlling parameters must be adjusted anew.

[0004] This adjustment would include the said zero point, the intensity of the regulation, (i.e., the amplification of the variable speed motor control), the setting of band fineness, that is, the length related thickness of the band, and the correction values in the case of a slow run of the machine. Actually, sensors measure the band thickness. As a matter of common speech usage, “band fineness” and “band thickness” are employed as synonyms.

[0005] A possibility for the determination of at least the optimal regulation intensity is made available by the so called “bands-test”. With this testing, it is expected that inherent machine behavior and material-specific idiosyncrasies would be reliably detected independently of the regulation. The bands-test is carried out in a random sampling manner and executed manually for the determination of the correct control of thickness variation of the fiber band(s). In conducting this testing, first, the normal number of fiber bands present (for instance, six bands) which are being drawn is determined, and at the same time the variations thereof are controlled. Thereafter, one of the bands present is removed, and the remaining bands are so subjected to control, that the required thickness of a band when the normal number of bands are present is achieved. In a converse example, to the original number of the present fiber bands (in the example, the named 6 bands) an additional band can be added. The bands are again so controlled, that the band thickness appropriate to the original band number is obtained. From each three steps, samples of a specified length, for instance, of 25 m, are taken out and weighed. (In the speech of the practice, the expression “ktex” is used for the term “band-weight”). This procedural method is repeated a number of times to achieve a statistically secured value. Deviations of the A %-value (A %=percent-based, band thickness deviation) of the drawn, controlled band are determined from the obtained mean values, which represent a three-point measurement. The described bands-test is repeated, until an acceptable A %-deviation (for example, <0.1%) is attained. The procedure and the basis for the calculations are as carried out for the draw frame RSB-D 30 of the Firm Rieter described in the brief operational manual under Item 2.31, Section 3C/100 to 3C-102.

[0006] The bands-test described requires a large investment in time and materials. In the case of the exchange of small batches, such an investment is unwarranted. An additional problem is, that where critical fiber materials are involved, the testing conditions must be held within very exact limits. For example, under certain circumstances of humidity in the working space, fiber material picks up moisture in different quantities, which can falsify the comparativity of the test values. In DE 42 15 682, teaches a method of conducting an automatic bands-test, wherein a transient signal regarding a thickness portion can be directed to an on-line execution of a bands-test. This procedure has, however, the disadvantage, that when regulation fluctuates for a long time, the regulating parameters, the regulation zero point and the intensity of regulation, become biased because of the measurements at the output end of the draw frame and in this way, both an interrupted and therefore a not necessarily desired regulation behavior follows, which can bring about a chaotic control situation. In an alternative variant of the DE 42 15 682, the transient signal generates a reserve band by a periodic infeed, which adds to causing this procedure to also be complex and time consuming.

[0007] A further complicated adaption of the parameters for regulation is necessary, if the values of the band weight sensors or band thickness sensors at the draw frame feed end, during a specified slow run of the machine (as compared to normal speed, i.e., 800 to 1000 m/min) must be corrected because of characteristics of the fiber material. In accord with the previously described mechanical feeler-roll system at the entry to the draw frame, it became evident, that the feeler roll measurement differs as the speed varies. Further, the penetrating depth of the feeler roll is dependent upon the kind of fiber, even when thickness does not change. On this very account, previously, with the mentioned Rieter machine, the cited “Adaption to Fiber Type” is carried out. Refer to the brief operational manual for the above mentioned draw frame RSB-D 30 of the firm Rieter under Item 2.30, Section 3C/99. In this reference is to be found, that the actual band-thickness at the draw frame output end, (that is, delivered band thickness) with a slow running machine, can be compared with the same delivered band thickness, but processed at a normally fast delivery speed. As part of this comparison, the effect on the band exiting from the draw frame because of weight differentiation was examined. This examination comprised producing a band sample of, for example, 10 m long at normal operating speed and subsequently, producing the same during a slow run, the latter being perhaps one-sixth of the normal speed. From the result of the weight comparison of the said samples, the operating person, having the predetermined standard values (“X % difference between the two actual band-thicknesses somewhat corresponding to a change as referred to in “Adaption to Fiber Type” of y %) can input on an operation panel the correction for measurement error in the values for the slow run of the machine. This procedure is also time consuming, restricts production and is costly.

[0008] Thus it is the purpose of the invention to improve an apparatus, that is to say, a procedure of the kind mentioned in the introductory passages, in such a manner that a rapid optimization of regulation parameters of spinning machines and, in particular, of regulated draw frames can be carried out.

[0009] This purpose is achieved by an apparatus or employing a procedure of the kind mentioned in the introductory passages, through the features of respectively claim 1 or claim 17.

[0010] The invention offers the advantage of making possible a more rapid optimization of the parameters for the regulation—as also especially for the regulation intensity—of the dynamic behavior of the regulated stretch, especially upon change of batch and/or material. At the same time it becomes possible to quickly detect by computation faulty measured values upon machine start-up and to correct the same by means of the units employed for control and/or regulation. The computing means, i.e. the microprocessor, required for this task can form a separate entity or be integrated into another central computer station or even be placed in an expanded sensor apparatus.

[0011] Advantageously, as a first draw frame machine, the normal running of a draw frame will be considered. By means of a comparison of the band thicknesses, or the variance of the band thicknesses, being delivered from the delivery end of a first machine (here draw frame), during normal operation to those in a second machine running at slower operation, extrapolation will show to what extent influences inherent in material and/or machine internals will exert on the product. If more exact correction becomes necessary, then also third and fourth (etc.) machines can be brought into the evaluation.

[0012] Advantageously, in the following, the normal (high speed) of the first draw frame machine will be employed in the discussion and computations. By means of the comparison of the band thicknesses, or the thickness deviations thereof, which are measured at the output end of the of the draw frame in normal running speed to that of the second non-normal machine, as said, the extrapolation will show how great the inherent influences of material or machine are on the total regulation. If more exact corrective measures are needed, then third and fourth draw frame machines can be brought into the computations, wherein these third and forth machine are to represent a non-normal running speed. (The corresponding base value, for normal operation, remains unchanged as being the first draw frame, i.e. the measuring point for a normal high speed run.)

[0013] Contrarily, it is also possible, not to designate the first draw frame machine as being the draw frame in normal operation as, but rather to select a different machine from at least a second draw frame machine, in order to determine optimized regulation in the case of special conditions.

[0014] The apparatus in accord with the invention, as well as the corresponding procedure, permits itself to be most advantageously applied, if the at least one sensor at the output end of the draw frame furnishes a very high degree of measuring exactness. Most appropriately, at the output end, would be a nearly ideal measuring sensor, which measures the band thickness and the variations thereof with very little error. The permissible error should not be greater than 0.9%. The parameters for the draw frame can be adjusted very well when based on very exact measured values at the draw frame output end. Especially for such measuring demands, preferably a microwave sensor (see, for example, WO 00/12974) with a hollow space resonator can be applied at the draw frame output end. In the case of a microwave sensor, then the object of measurement is the weight of the band, instead of the thickness of the band. If, in the realm of this invention, where “band thickness” is spoken of, this also includes, in the case of the microwave sensor, also the concept of “band weight”.

[0015] In an especially preferred embodiment variant of the invention, is simulated the addition or removal of a single presented band or a principally optional part of one or more presented bands. This means, that for the optimization of the regulated product, the active, i.e., the actual addition or removal of a single presented band to the actual number of presented bands can be eliminated. Concretely said, in the speech of the invention, what is simulated by at least one second draw frame machine, is the presentation (or removal) of one or more fiber bands or a non-integer number of fiber band parts, to the actual present band count, respectively in an additional or subtractive manner.

[0016] The previously stated simulation of the bands-tests has the advantage, that—contrary to the above mentioned DE 42 15 682 A1—the true band characteristic has no importance. It is not necessary to bring in a transient signal into the presented bands or a reserve band in order to carry out the bands-test. Instead of this, the execution of the simulation at any optional point in time is sufficient.

[0017] In the case of such a simulation, advantageously, control signals are transmitted to the regulation drive of the draw frame, wherein the electrical voltage of the actual variations of the band thickness—determined from the signals of the at least one of the sensors located at the feed end of the machine—is increased or decreased in the amount of the voltage corresponding to the simulated additive or subtractive fiber band portions. If, at the same time, it has been simulated that seven bands have been presented to the draw frame, when, in reality, only six bands have been introduced, then, the corresponding draw frame rolls are controlled, as if seven bands were present. The band, which is exiting the draw frame at the output end, accordingly becomes thinner in its cross-section than a normally regulated band—simulation being withheld—wherein the control signal would have corresponded to the true number of bands. If, for example, the set band-thickness should read 5 ktex at six presented bands, then the set band thickness in the case of a simulation of seven presented bands would be 5 ktex·5/6. If the presentation was simulated at 5 bands, then the set band thickness would be 5 ktex·7/6. The measured actual band thicknesses with the set band thicknesses are now advantageously, by means of iterative changes of the regulation intensity, compensated in such a manner, until the actual band thickness essentially agrees with the set band thickness.

[0018] This means, that the actual band width deviation is very small. As will be explained below, the actual band width deviation is to be employed as a computational value. In order to proceed in this matter safely, the simulated bands-tests can be repeated correspondingly often, until a sufficiently exact agreement between the actual and the set values is transmitted to the delivered band thicknesses. In such a case, for example, threshold values may be established, wherein, in an understepping of the same, no further simulations need be undertaken.

[0019] With the corrected regulation intensity, which presents a factor, then the characteristic curve of the variable speed motor drive for regulation can be corrected, especially in its slope. Note should be taken that the characteristic curve changes in accord with each adjusted delivery speed on the machine and for the current delivery speed can be computed and stored.

[0020] The procedure of the bands-testing is here more explicitly described with the aid of an example.

[0021] Upon the presentation of (assumed) several fiber bands, the band thickness deviations as measured by a sensor at the draw frame feed end, designated by m1, which is composed from the mean band weight mdoubling and the deviation thereof Δm1 is determined and converted to an electrical signal Ui (which is composed from Udoubling and ΔUi). The measurement signal portions, which the dynamic portion ΔUi reflects, are brought in for the regulation. The measurement signal of the mean band weights mdoubling represents the so-called 0%-compensation (operational point).

[0022] For the simulation of the additives of a presented band, the electrical voltage Udoubling, which represents the mean band weight, is increased by the direct current amount ΔU+l Band which represents the addition of one fiber band. However, an advantageous offer is, that this increase can be limited by principally the maximum occurring band thickness deviations, for example, +10%. In case six bands are presented, then the addition of one band would indicate a deviation of band thickness of 16.7%. Upon the limitation of 10%, then the presence of a complete band would not be simulated, but only for about 10/16.7 of a fiber band.

[0023] For the sake of simplicity, however, in the following, for the simulation below of the addition (and the subtraction) only an entire band will be considered.

[0024] In the case of the simulated addition of a band, the regulatory drive signal receives control signals which represent the potential ΔUi of the actual band thickness deviations plus the simulated additional direct current amount of ΔU+l Band. From this, the result is an actual thinning of the drawn fiber band as compared to the set band thickness by adding a proportional amount of ΔU+l Band to the amount of the direct current potential.

[0025] For the determination of the percentage related, actual band thickness deviations (A %ist) in accord with the basis of computation for the bands-test, there are at least two computational methods, independent of each other. The first possibility rests on the formation of a set-quotient, which is derived from the following equation:

\begin{matrix} A %_{soll} = \frac{T_{soll, Δ U_{+ 1 Band}}}{T_{N, D}} & (1) \end{matrix}

[0026] For the determination of the actual A %ist a second equation is put forth:

\begin{matrix} A %_{ist} = A %_{soll} - \frac{T_{ist, Δ U_{+ 1 Band}}}{T_{N, D}} \cdot 100 & (2) \end{matrix}

[0027] Wherein:

[0028] Tsoll,ΔU+lBand: Set band thickness of sim. added band,

[0029] Tist,ΔU+lBand: Actual band thicness of sim. added band,

[0030] TN,D: Actual band thickness of normal drawn bands

[0031] Advantageously, a plurality of values are determined for the actual band thickness per draw frame machine, for example, respectively three values for a fiber band length of 20 m. In the concrete example, this means, that three values for six fiber bands (without simulation) and three values for seven fiber bands (six actually present and one additionally simulated) are measured and thus the arithmetical mean value is determined.

[0032] With the aid of Equation (2) it is possible to compute the actual value associated with the A %-value, i.e. A %ist. In case this actual value falls above the threshold value, then, preferably, the regulating intensity is changed and advantageously the simulated bands-test is carried out again.

[0033] Additionally, one or several other band presentations can be simulated, for example, the removal of one band, in order to calculate the thereto appropriate A %ist-value. It is also principally possible, to carry out the simulation largely for one situation, as example, essentially a second draw frame machine (addition or subtraction of a fiber band or fiber section) and to compare the result advantageously with that of the actual presented fiber bands. Independent thereof, as to on how many different draw frame machines the measurements were performed, the procedure is preferably iterative. The reason for this is, that the A %ist-value for the at least two draw frame machines should be computed and if necessary, thereafter the regulation intensity be changed, in order, that by means of these new conditions, the corresponding A %ist-value can be calculated, until this has understepped a given threshold and therewith, the corrected regulation intensity, that is, the optimal adjustment, has be found.

[0034] A second, alternative possibility for the calculation of the true A %ist-value rests first, upon the recalculation of the actual band thickness, which has been measured at the delivery end of the draw frame as a result of the simulated addition of one band, namely

\begin{matrix} T_{ist, Δ U_{+ 1 Band}}, for the quotient \frac{T_{N, D}}{T_{soll, Δ U_{+ 1 Band}}} : T_{ist, Δ U_{+ 1 Band}} = T_{U} = T_{ist, Δ U_{+ 1 Band}} \cdot \frac{T_{N, D,}}{T_{soll, Δ U_{+ 1 Band}}} & (3) \end{matrix}

[0035] The determination of the A %-value is don in accord with the following condensation:

\begin{matrix} A %_{ist} = \frac{T_{U} - T_{N, D}}{T_{N, D}} \cdot 100 & (4) \end{matrix}

[0036] For the simulation of the removal of a presented band, the electrical potential, that is, Udoubling, which represents the mean band weight is reduced by the direct current potential amount of ΔU−lBand. In this manner, the regulation drive receives control signals, which represent the signals ΔUi of the actual band thickness variations, as well as the simulated direct current potential of ΔU−lBand. From this, the result will be a thickening of the drawn fiber band as compared to the set-band thickness by an amount proportional to the equal potential amount ΔU−lBand+10%.

[0037] The computation of the actual A %-values, i.e., (A %ist), is carried out advantageously in accord with the equation (2) or (4), wherein the corresponding band thicknesses, advantageously averaged over a plurality of determined measurements, are taken into consideration. In a preferred method, the band thickness is measured by a simulation of an additional fiber band (second draw frame machine) and by the band thickness in a simulation of one removed fiber band (third draw frame machine) as well as the band thickness being measured in a normal operation (first draw frame machine). Advantageously, in this method the mean values are determined by some three measurements. With the equation (2) at hand, for example, from these (determined) band thicknesses, the A %ist-values are determined respectively for the greater and the lesser number of fiber bands. If these A %ist-values exhibit different prefixes, which is synonymous with an over-regulation in one case, and an under-regulation in the other, whereby, advantageously, a mean value can be formed. This is also described in the conventional bands-test in regard to the short operational manual under Item 3.31, Sec. 3C/101. The regulation intensity is then preferably changed in iterative processing, to the point where this means value, and/or the two A %ist-value understep the specified threshold values.

[0038] For the computation of the A %-values, a computer unit is necessary. The execution of the automatized, or the automatic bands-tests by means of simulation is accomplished in a preferred variant before a batch change. Alternatively, or additionally, the simulation bands-test is simulated at definite time intervals and/or following the occurrence of certain happenings, for instance, upon the drift of the A %-value above a specified drift allowance threshold.

[0039] In a second advantageous formulation of the invention, erroneous measured values are corrected by a slow run of the machine, that is to say, especially during start-up or at shut-down. This can occur without the necessity of carrying out the mentioned “Adaption to Fiber Type”, which entails extensive laboratory testing. In general, the optimal regulation parameters are not known as a function of the delivery speed below a specified delivery speed. By the use of, for example, a groove-feeler roll pair at the feed end during a slower run of the machine (start-up and stopping the machine), false measurement values are the result because of, as compared to the higher production speeds, the differing penetrative behavior of the feeler roll into the individual or collective fiber bands. Only by higher delivery speeds, or in an extreme case, only by reaching the final delivery speed, can one rely on any constancy in the regulation parameters. On this account, when measurements are carried out during the stopping and the starting of the machine, these must be such that they can only be counted on for extrapolation or estimation toward optimal regulation parameters. To this end, measurements, with the aid of at least one sensor on the draw frame delivery end, are at least necessary at two speeds.

[0040] Advantageously, as this is done, the two speeds are, first, a speed at a defined slow run of the machine (that is to say, a second draw frame machine), this being, for example ⅙ of the operational speed and second, the higher normal operational speed (of the first draw frame machine) itself Because of both speeds, the presented fiber bands are drafted under regulation. The currently band thicknesses produced under these conditions, are detected by the aid of at least one sensor in the exit from the regulation stretch, and, if necessary, the said “Adaption to Fiber Type” operation is automatically activated in such a way, that the regulation of the faulty measurement results of the at least one sensor at the draw frame feed end is compensated for by the slow run in comparison to normal operation, i.e., the rapid run. Involved here is also a correction factor which is determined by the processor and with this factor, the measurement errors arising in a speed reduced from the normal speed are corrected.

[0041] Instead of the said two-point measurement, that is, measuring in first, a defined slow run and second, in normal operation, it also obviously becomes possible to employ measured values from many other speeds which have been advantageously reduced from the normal speed. In this way, the precision of the correlation or function between optimal regulation parameters and the delivery speed can be increased. For example, to this end, it is possible that several operational conditions of the draw frame at coming up to speed and/or at shut-down of the textile machine can be employed which offer slower delivery speeds as compared to that of normal operation. The present day speed of the processors makes it possible, during coming up to speed or approaching shut-down, to capture many points of measurement which allow a very exact approach to the functional curve.

[0042] The results from the simulated bands-test and the “Adaption to Fiber Type” can be electronically stored, in order to make them available upon a repetition of like conditions. In any case, the simplicity and the rapidity of the invented solution makes such a procedure not unconditionally necessary. In this case, for example, a plausibility control is carried out.

[0043] Instead of an automatic adjustment to the optimal regulation parameters, a manual adjustment or correction of this or individual parameters is possible. In this case, these adjustment values are preliminarily proposed for the machine, and the operator can then install the adjustments in a corresponding operations panel, which is advantageously combined with a display apparatus. In another alternative, first, a plausibility monitoring is run through the machine and upon a positive result, the optimization of the regulation parameter(s) is undertaken automatically. Another alternative, after a positive plausibility monitoring, such an optimized machine adjustment is proposed to the operator. The operator can even himself, additionally or alternatively, carry out such a plausibility control on the basis of his own experience and/or with the aid of a control manual.

[0044] Advantageous developments of the invention are characterized by the features in the subordinate claims.

[0045] In the following, the invention is more completely described abd explained in greater detail with the aid of the drawing. There is shown in:

[0046]
FIG. 1 a circuit arrangement of a regulated stretch machine in accord with the invention,

[0047]

FIGS. 2

a
, 2b a view of a bands-test, in 2a in accord with the state of the technology and in 2b in accord with the invention, wherein the respective signals are indicated on the entry sensor and at the output sensor,

[0048]

FIGS. 3

a
, 3b a simulation of an addition to, and a detraction of a fiber band by an appropriate potential, applied in 3a at the input of the FIFO storage and in 3b, applied behind the FIFO storage and showing as well the actual band thickness resulting therefrom as measured by an output sensor,

[0049]
FIG. 4 a graph with the set band thickness with and without simulated fiber band pieces, showing dependency of the set band thickness deviation (A %set),

[0050]
FIG. 5 a presentation of the error to be corrected at the entry sensor during slow delivery speeds, and

[0051]
FIG. 6 a correction of the said error by means of an automatic “Adaption to Fiber Type”

[0052] Schematically, in the diagram of FIG. 1, is presented the control principle of a regulated draw frame 1 as an example. At the entry to the draw frame 1 the band-thickness of the bands 2 passing through—in this case, six bands 2—are mechanically measured by a groove/feeler roll-pair 3, which is located immediately before a band collection funnel 18. After passing through the said funnel groove/feeler roll-pair 3, the fiber bands 2 are again permitted to spread out, in order to enter the draw frame. The measurement values of the groove/feeler roll-pair 3, which is serving as the fiber feed sensor, are converted in a signal transducer 4 into electrical potential values, which are conducted to a FIFO (First In, First Out) designed memory module 5. This FIFO-memory 5 relays the measurement potentials, with the aid of a pulse generator 6, which has a specified time delay to a set value stage 7. The FIFO-memory 5 and the set value stage 7 are a part of a regulation computer 17 (which is shown in a dotted line block). The set value stage 7 contains in addition to a lead-tachometer 9, a lead potential, which is a measure for the speed of rotation of the lower roll of a delivery roll-pair 22, which roll is driven by a main motor 8. Subsequently, in the set value stage 7, a set potential is computed and transmitted to a control and/or regulation unit 10. In the said control and/or regulation unit 10, a comparison is made between the set and actual values. The actual values of concern here originate from a regulator motor 11, which transmits said actual values to an actual value tachometer 12. This tachometer 12, in turn, sends the corresponding actual potential to the control and/or regulation unit 10. The set to actual value comparison made in the control and/or regulation unit 10 is made use of for the purpose of providing the regulation motor 11 with an entirely defined speed of rotation, which corresponds to the desired, draft changing speed of rotation. The regulator 11 is connected to a planetary gear drive 13, which receives its drive from the main motor 8. By means of the planetary gear drive 13, the speed of rotation of the lower roll 20 of an feed end roll-pair and the under roll of a mid-point roll-pair 21 is so altered, that a band equalization is established at constant speeds of rotation of the delivery pair 22 (constant delivery speed). The fiber matting, i.e. the fiber bands, on this account, are drawn first in the pre-draw section between the input roll-pair 20 and the mid roll-pair 21, and drawn second in the main draw field (and, indeed at the regulation application point) between the mid roll-pair 21 and the delivery roll-pair 22. Also, the groove/feeler roll-pair 3 is driven with the aid of variable speed motors 8, 11.

[0053] The band thickness, measured at the groove/feeler roll-pair 3 (inlet sensor) serves for the reference regulation band thickness. Because of the fiber band transport from the groove/feeler roll-pair 3 to the draw frame, which comprises the entry, mid and delivery roll pairs 20, 21, 22, a dead time is computed, which corresponds to the time delay in the FIFO-memory. The theoretically computed dead time is continually corrected, with consideration given to the dynamic drive of the regulation motor 11 and the drive-line belonging thereto. The speed of rotation for the regulation motor 11 as a control value is determined by the control and/or regulation unit 10, which processes the actual band thickness of the fiber band, the set value of the band thickness (as a guide size) and the speeds of rotation of the main motor 8 and the regulator motor 11. By means of the proportional superimposition of the speed of rotation of the main motor 8 and the regulation motor 11, and taking into consideration the said dead time, the band thickness is regulated in the draw frame at the regulation application point, which lies between the middle roll-pair 21 and the delivery roll-pair 22.

[0054] A component, in accord with the invention, of the regulated draw frame, which has been presented as an example, is at least a very precisely measuring band thickness sensor 30 at the delivery end of the draw frame, which, in the shown embodiment (FIG. 1) follows a band funnel 19.

[0055] A sensor 30 of this kind, for example, by means of microwaves, can very exactly measure the band thickness variations, which is also the band weight variations, of the fiber bands 2′ leaving the machine. Other principles of measurement with greater measurement precision are likewise possible, these being based on capacities, optical, acoustic and/or mechanical measuring methods. The at least one sensor 30, as is shown in an embodiment in FIG. 1, (solid connection line) is connected with the microprocessor 14 (in the regulation-computer 17), with the memory 15 interposed therebetween. The microprocessor 14 is in turn connected with the set value stage 7. In a further, alternative—shown in dotted connecting lines in FIG. 1—the sensor 30 is connected to a separate microprocessor 14′, with the memory 15′ interposing therebetween. This microprocessor 14′ itself, can be directly connected to regulation computer 17 whereby the connection continues to the set value stage 7. The microprocessor 14′ and the memory 15′ can be integrated into a second regulation computer 17′ for band monitoring, which is shown, again in FIG. 1, by a dotted outline. Alternatively, it is possible to integrate in the at least one sensor 30 itself, a microprocessor with a measured value memory (not shown).

[0056] A simulating bands-test is possible, by means of the at least one sensor 30. To execute this, the control and/or computer unit 10 is subjected to a short-period potential. This would be administered through the microcomputer 14, 14′, through the set value stage 7 or through a central computer (not provided in the embodiment of FIG. 1). This potential would represent the addition or the subtraction of one band or a portion of one band or several of the fiber bands presented to the draw frame. These potential signals are superimposed on those of the actual potential signals, which, for example, have been converted in the transducer 4 from the mechanical signals of the groove/feeler roll-pair 3. The control and/or regulation unit 10 provides an adjustment signal corresponding to the superimposed potential signals to the regulation motor 11, so that this exercises a corresponding draft on the fiber bands 2, which are now in the form of a spreadout fiber matting.

[0057] By means of the at least one sensor 30, which, in accord with the above requirements, permits very precise measurements, the examination can now be made, as to whether, and how the addition or the subtraction of fiber band portions has found its result in the correspondingly regulated fiber mat, i.e. fiber band 2′. This evaluation is undertaken in accord with the two presented alternatives in FIG. 1 by means of the microprocessor 14, 14′. In case the results of the investigation show, that the regulation intensity, i.e., the amplification of the regulation motor control is not optimally adjusted, then these must be changed, preferably on the grounds of the microprocessor findings by means of a corresponding command from said micro processor 14, 14′ released to the control and/or regulation unit 10. Preferably, subsequent to this, an automatic, that is simulated bands-test is carried out at least once, in order to determine the proper regulation intensity and, if necessary, the operation is to be repeated (iterated) for further optimization. The intermediate results can be stored in a memory 16, 16′ and again read out, since the said memory is in communication with the microprocessor 14, 14′. Likewise, in this memory 16, 16′ are stored the different determined factors of the regulation intensity obtained by the possibly different simulated draw frame machines. Subsequently, from these data, a possibly better evaluated mean or average value is determined, advantageously with the aid of the microcomputer 14, 14′.

[0058] Thus, the bands-test, formerly determined by complicated laboratory trials, is simulated by means of the addition or the subtraction of fiber band portions. The simulations would be more precise, that is to say, approached the regulation intensity more closely, if both the addition as well as the subtraction of fiber bands portions were simulated and, possibly, each time more measuring points (simulation of respectively different fiber band parts) were picked up.

[0059] Within the framework of the terminology of this invention, by here named “simulated bands-test” modus, preferentially designates the normal draw frame machine as the “first draw frame machine”, and the additional superimposition by means of potential signals of simulated added and/or subtracted fiber band portions as a second, third, fourth, etc. draw frame machine. If now, an additional or negative potential, representing a simulated fiber band part is applied, then besides the first draw frame machine, principally a second draw frame machine is now to be considered. Advantageously, however, both the addition as well as the removal of a fiber band or a fiber band part has been simulated.

[0060] In the FIGS. 2a, 2b respectively, first, the previous, conventional procedure of the bands-test is displayed in comparison with second, the simulated bands-test in accord with the invention. In the FIG. 2a, one sees in the left half of the illustration the presentation of six fiber bands 2—which represent the normal operation—as well as the presentation of five to seven actual fiber bands 2 along with the corresponding potential signals generated as measured on the feed end sensor 3. The regulation of the draw frame is so adjusted, that the measured potential signal at the delivery end sensor 30—shown as B in the right illustration half—and therewith the band thickness of the resulting fiber band 2′ is ideally represented as always uniform.

[0061] Contrary to this, in the case of the simulated bands-test in accord with the invention, as seen in FIG. 2b, the actual presented number of the fiber bands 2 is constant, for example six fiber bands with about 5 ktex, so that even the measurement potential at the inlet sensor 3 oscillates within a narrow range of measurement, namely “A” in the left half of the illustration. Contrarily, with the delivery end sensor 30, different degrees of band thicknesses are obtained, corresponding to the actually presented number of fiber band numbers added to, or taken from, the simulated band parts, as represented by “B” in the right half of the illustration 2b. The middle time point of the graph belongs to the six presented fiber bands 2 without simulation parts, the two graphs situated thereabove to an additional simulation of 10/16.7 indicating one completely removed fiber band (representing 10% or 16.7% set band weight deviation). The two lower measurement curves represent an additional simulation of 10/16, i.e., one added complete fiber band (representing −10%, or −16.7% set band weight deviation. In toto, in accord with this situation, then simulations must be run through five separate draw frames, whereby, advantageously, per draw frame machine, measurements from several determinations are undertaken. For example, per draw frame machine three or four times a 20 meter band must be measured and the result determined. The measurement values, corresponding to each measurement are, advantageously, intermediately stored in the memory 15, 15′ and then made available for the determination and further processing employing the microprocessor 14, 14′.

[0062] In FIG. 3a the simulated addition and in FIG. 3b the simulated subtraction of a fiber band is presented in reference to the actually presented number of fiber bands and, indeed, in respectively two alternatives. The left, dotted Y-axis represents here the predetermined control potential for the variable speed motor 11 and the right, full line Y-axis represents the actual band thickness as measured with the delivery end sensor 30. The control potential runs, in the normal regulation operation, about 0 V (in the case of the—not shown—use of single drives, the control potential would be, in normal operation not equal to 0 V). The graphs pertaining thereto, are likewise plotted respectively in dotted or solid lines. In the case of the one of the two alternatives, the fiber band, whether added or removed, can be realized by the superimposition of a corresponding pulse at a potential of about +0.7 V or −)0.7 V at the input of the FIFO memory 5. (See the potential jump at “1”.)

[0063] Because of the mentioned dead-time, i.e., time delay in the memory 5, this being “FIFO delay” the drop-off in the case of a simulated, additional fiber band (FIG. 3a), that is, the corresponding rise by a simulated removed fiber band (FIG. 3b) only registers with the corresponding delay registered by sensor 30 (covering the distance of the fiber band 2 from the feed end sensor 3 to the regulation onset point, which represents the FIFO-delay plus the covered distance from the regulation point inset point to the delivery end sensor 30).

[0064] Otherwise, this is in the case of a possible superimposition of the simulation potential at the output side of the FIFO-memory 5 (or at the input or output of the set value stage 7 or yet at the input of the control and/or regulation computer 10)—see the respective potential jump at “2”—whereby, because of the short travel between the draw frame and the delivery end sensor 30 the corresponding signal is received with only a short delay at the output of the delivery end sensor 30.

[0065] In that particular time delay, which is designated as “evaluation” measuring points were picked up by the sensor 30, specifically a measuring point denoting a band length of 20 m. The determined value provides the set band thickness Tist,ΔU+lBand or Tist,ΔU−lBand, as appears in Equation (2). As has been explained above, advantageously, because of the spreading of the measurement results, the measurements at each point of operation, that is, each draw frame machine are repeated and subsequently a mean value for the set band thickness is reprocessed.

[0066] Considering now FIG. 4, in the following, with the incorporation of the equations (1) and (2) above, the principle of the simulated bands-test utilizing an example of a six-fold doubling will be described in additional detail. The assumption is made here, that possibly five, determined measurements, representing five different draw frame machines were employed for the establishment of a function, which represented the set band thicknesses, dependent upon the set band thickness deviation (A %soll). The set band thickness of the resulting fiber band 2′ by the drawing of six fiber bands 2 without simulation (TN,D) should run, ideally, with a presentation of 5 ktex. The set band thickness A %soll resulting from one simulated additional fiber band Tist,ΔU+lBand calculates out to 5·5/6=4.167, so that in accord with Equation (1), then (A %soll=−16.7%). Following the example of FIG. 4, then the removal of one fiber band (A %soll=16.7%) as well as the addition of one fiber band part representing A %soll=−10% and the removal of one fiber band part represents A %soll=10% simulated. According to this, in FIG. 4, the curve shows the set band thickness Tsoll plotted against the set band deviations (A %soll).

[0067] In principle, now the set band thicknesses Tsoll in accord with FIG. 4, with the set-band thicknesses Tiist can be compared together as in FIG. 2. From the computational standpoint, with the usage of Equation (2) and with the aid of the A %soll-value for the second, third, etc. draw frame machine, a mean value can be computed. Subsequently, the regulation intensity of the draw frame machine is changed and once again the measurements of the corresponding set-band thicknesses (proportional to the measurement potentials at the delivery end sensor 30) are carried out, until the corresponding Aistl-value understeps a specified, predetermined threshold value.

[0068] By means of the invented apparatus, also preferred is a correction of the measurement value error of the feed end sensor 3, in the case of slow delivery speeds, these being possible especially at start-up and shut-down. The first draw frame machine represents, in this matter, the normal operation of the machine with the customary high delivery speeds (these being today in the area of 800 to 1000 m/min), conversely, the second draw frame is operated in a slow run. Especially in the case of mechanically feeling feed end sensors, such a that shown in FIG. 1 as the groove/feeler roll-pair 3, the penetrative depth of the feeling element into the one or more presented fiber bands 2 is dependent upon the speed of these bands, so that measurement error can arise which must be corrected in the slow speed operation.

[0069] In FIG. 5, this matter is presented to show greater detail. The band thickness measured at the feed end by sensor 3 (solid line), and the band thickness measured by the sensor 30 at the delivery end (dotted line), are presented for the states of start-up, normal operation, and shut-down of the machine. The whole band thickness of the here six presented fiber bands should show a constant 30 ktex, wherein this value is measured during normal operation. Upon the start-up and the shut-down of the machine, the rolls of the groove/feeler roll-pair 3 penetrate deeper into these six bands, so that a band thickness of lesser measure results than is the case during normal operation. This situation shows up as the registration of a thin spot in the fiber band. Reacting to this, more band material is fed into the draw frame, in order to obtain a uniform fiber band. As a consequence at the delivery end sensor 30, the fiber band is detected to be thicker. The invention allows this error to be corrected without the necessity of laboratory checks.

[0070] This correction can be undertaken, in accord with the invention, if one or more draw frame machines are operating slower than the more rapid rate designated as normal operation, the currently produced band thicknesses are detected by the at least one delivery end sensor 30. As an embodiment example, shown in FIG. 6, three measuring points are picked up at different slow delivery speeds, along with one measuring point at the normal high speed at which latter no measuring error can occur at the feed end sensor 3. Fortunately, in this case, mean values can also be determined by a plurality of measurements under the same circumstances. The dotted line clarifies the course of the curve, wherein, at each speed of delivery, measuring points were picked up.

[0071] With the aid of the microprocessor 14, 14′, the latter as allowed by the alternate in FIG. 1, the measured values are immediately evaluated, which indicate the deviations of the band thicknesses measured on the delivery end sensor 30 during the various speeds of delivery. By the deviation of the band thicknesses, the so-called “Adaption to Fiber Type” can be automatically undertaken in accord with the invention, in such a manner, that the regulation computer 17 compensates for the erroneous measurement results of the at least one feed-end sensor 3 at the one or more slow run speeds by comparison to the normal operating speed (high speed running), whereby the registered measurements signals are corrected and thus the regulation motor 11 is correspondingly controlled. In this matter, advantageously a correction factor or a correction function is determined, for example by means of the microprocessor 14, 14′ and therewith the measurement error in the speed operation counter to the normal operation is corrected. The correction factor and/or the correction function can be input into the memory 16, 16′.

[0072]
FIG. 6 shows, for instance, how a correction function of this kind can be determined. The four said measuring points are respectively joined by straight lines, wherefrom a non-continuous function arises. The values of the corrections functions can then, upon start-up or upon shut-down of the machine be applied to the momentary delivery speed, in order to accordingly control the regulation motor 11. In a simple alternative, principally a measurement point at a low speed is taken (in accord with the state of the technology, in which, in any case, gravimetric laboratory weighing must be carried out on the drawn fiber band) and this measuring point approaches that measuring point at which no measurement error can occur by a single straight line. This straight incremental line then provides a correction factor. Instead of such a linear approximation, it is also possible to combine the measuring point with a constant function, whereby the exactness of the correction can be increased. FIG. 6 likewise shows, that the resulting fiber band with the correction in accord with the invention possesses an essentially constant band thickness of 5 ktex (solid line graphing.)

[0073] With an alternative regulating system (not shown), the planetary gear drive can be dispensed with. In this case predominately, single drives are installed. The drive, of the under inlet roll and the under mid-roll is carried out directly by a separate variable speed motor. The exact synchronization of the main motor, which provides the delivery roll with a constant speed of rotation, and the variable speed motor is taken care of by a draft microprocessor. The speed relationship of the two motors determines the draft. Also, in the case of this regulation system, the described invention is accordingly applied.

[0074] Before or after the carrying out of each optimizing step, or even at the conclusion of the optimization of the regulation adjustments, the achieved results can be confirmed by the user, for instance, on a machine display such as the display apparatus 25, which, in FIG. 1, is shown connected to the regulation computer 17. The double arrow between the regulation computer 17 and the display apparatus 25 make clear, that first, data from the regulation computer 17 can be transmitted to the display apparatus 25 and that second, on the display apparatus 25, for instance, a touch keyboard can be placed in order to send commands to the regulation computer 17. In this way, the determined values can be employed by the user, for example, for a plausibility control. As an alternative, the display apparatus and an input apparatus can be installed separate from one another.

[0075] After the optimizing, preferably an automatic can exchange at the delivery end could be installed, so that in the cans, which are subsequently to be filled, only a uniformly drawn fiber band will be laid down, which is optimal over its entire length. Moreover, on the machine display, advantageously notice can be exhibited, that the test material is to be removed.

[0076] Conclusively, thus the invention makes possible especially, that the bands-test can be considerably automatized. As another advantage, a method for the correction of the band error is proposed, which correction can be effective at the start-up and shut-down of the machine during a defined slow run of a regulated draw frame, as compared to the normal operational speed, with consideration given to the fiber material to be processed. As this is done, the processes are carried out in an advantageous variant fully automatically. Especially after a batch change, first the mechanical parameters are optimized and the desired band thickness is obtained, before—advantageously in this succession—the “Adaption to Fiber Type” and the simulated bands-test is undertaken. The point of regulation—advantageously subsequently—can be determined by the CV-value, as this is set forth in the EP 803 596 B1.

[0077] The invention has been described in regard to a regulated draw frame. The invention can be used, however, on a carding machine or a combing machine with a regulated draw frame. Likewise, the invention can be applied to carding or combing machine with subsequent stretch machine having a regulated draw frame.

Claims

1. An apparatus for the optimization of the adjustments for regulation of a spinning works machine with a regulated draw frame, inparticular, a regulated draw frame machine (1), a carding machine or a combing machine, to which are continuously fed one or more fiber bands (2), said apparatus having at least one sensor 3 situated ahead of the draw frame for the capture of values of the band thickness of the one or more infeeding fiber band (2), with at least one sensor (30) located at the delivery end for the determination of the value of the band thickness of the resulting fiber band (2′) in a first draw frame machine as well in a second specified draw frame machine, whereby the second draw frame machine does not represent the normal delivery speed of the draw frame, and having a microprocessor (14; 14′) for the comparison of the values captured by the at least one delivery end sensor 30 with the at least two draw frame machines, and having a control and/or regulation unit (10) for the adaption of the regulatory adjustments on the basis of such machine characteristics and/or fiber band material characteristics as influence measured values.
2. An apparatus in accord with claim 1, therein characterized, in that the normal operation of the draw frame, with its conventionally high delivery speeds where fiber band production is concerned is to be considered as a first draw frame machine.
3. An apparatus in accord with one of foregoing claims, therein characterized, in that the at least one delivery end sensor (30) is a microwave sensor.
4. An apparatus in accord with one of the foregoing claims, therein characterized, in that, a transient band-presentation of one or more fiber bands or incomplete fiber bands, in addition to, or subtracted from the actual presented fiber bands (2) can be simulated as at least one second draw frame machine (“simulated bands-test”), particularly in order to correct the amplification factor for the draw frame regulation, i.e. regulation intensity.
5. An apparatus in accord with claim 4, therein characterized, in that by means of the control and/or regulation unit (10), potential-control signals can be given to the regulating motor (11) of the draw frame machine, which represent the simulated added or removed fiber band parts, and which potential signals are added or subtracted respectively to or from those electrical potential signals (Ui), which represent the actual band thickness deviations determined by the at least one feed end sensor (3) situated before the draw frame machine.
6. An apparatus in accord with claim 4 or 5, therein characterized, in that one microprocessor (14, 14′) is enabled to compute the actual value of the A %-value from the set-band thickness and from the measured actual band thickness in the case of the simulation of the addition and/or subtraction of fiber band parts (=second draw frame machine) as well as from the actual band thickness at the drafting of the real number of fiber bands (=first draw frame machine without simulation).
7. An apparatus in accord with claim 6, therein characterized, in that with measurements in a first and in a second draw frame machine, the intensity of regulation can be re-adjusted automatically or manually, until the actual value of the A %-value reaches a minimum value or understeps a specified value.
8. An apparatus in accord with claim 6, therein characterized, in that by measurements in more than two draw frame machines, the regulation intensity can be re-adjusted automatically or manually, until the actual value of the A %-value or an average value from this A %-value has reached a minimum value or understeps a specified value.
9. An apparatus in accord with one of the claims 1 to 3, therein characterized, in that a slow-run operation with a slower delivery speed as compared to the normal operation (that of the first draw frame machine) may be made available as at least one second draw frame machine.
10. An apparatus in accord with claim 9, therein characterized, in that deviations between the measured actual band thickness at the draw frame delivery end in the at least one second draw frame machine and the first draw frame machine can be converted into a corresponding control of the regulation drive (11) in the second draw frame machine, so that the measured actual band thicknesses on the draw frame delivery end for the first and the second draw frame machine are essentially equal in size, or their difference lies less than a specified threshold value.
11. An apparatus in accord with claim 9 or 10, therein characterized, that in one or more test runs of a microprocessor (14, 14′) one or more correction factors and/or one correction function can be determined, and can be stored in a memory (16, 16′), and which, in the slow run operations which follow thereafter, especially during the coming up to speed at start-up and during the stopping of the machine, can be employed for the control of the regulation drive (11).
12. An apparatus in accord with one of the foregoing claims, therein characterized, in that the comparison can be carried out at predetermined time intervals, between the at least first and second draw frame machines upon a batch change, as well as at the occurrence of predetermined occurrences.
13. An apparatus in accord with one of the foregoing claims, therein characterized, in that in accord with the optimized machine adaptations in accord with the foregoing claims, a can change at the machine delivery end is permissible.
14. An apparatus in accord with one of the foregoing claims, therein characterized, in that change of the regulation adjustment can carried out automatically or manual adjustments to the machine by the operator.
15. An apparatus in accord with one of the foregoing claims, therein characterized, in that, on the machine is provided a display apparatus (25) for the announcement as to whether or not changes should be made, and if positive, announces which changes of the regulation settings should be made based on the machine characteristics and/or the fiber band material characteristics which influence measured values.
16. A spinning works machine, in particular, a regulated draw frame (1), a carding machine or a combing machine with an apparatus in accord with one of the foregoing claims.
17. A procedure for the optimization of the regulatory adjustments of a spinning machine, especially a regulated draw frame (1), a carding machine or a combing machine, which procedure encompasses the following steps: one or more fiber bands (2) are continually fed to the draw frame, at the infeed end of the draw frame, with the aid of at least one sensor (3), values are captured for the band thickness of one or more of the fiber bands (2), at the delivery end of the draw frame, with the aid of at least one delivery sensor (30), values are captured of the band thickness of the resulting fiber band (2′) in a first draw frame machine and in at least one second, defined draw frame machine, wherein the second draw frame machine does not represent the normal operation of the draw frame, and the said captured values of the at least two draw frame machines are compared with one another with the aid of a microprocessor (14, 14′), in order to undertake adaption of the regulating adjustments on the basis of the machine characteristics and/or fiber band material properties which can influence the said measured values.
18. A procedure in accord with claim 17, therein characterized, in that a short period presentation of one or more fiber bands or of a non-integral number of fiber bands, in addition to, or in subtraction from, the actually presented fiber bands (2) can be simulated (simulated bands-test), as at least a second draw frame machine, especially in order to correct the amplification factor for the draw frame regulation (“regulation intensity”).
19. A procedure in accord with claim 18, therein characterized, in that on the regulatory drive (11) of the draw frame, short term potential control signals are issued, which represent the simulated added or subtracted fiber band parts, and are added to, or subtracted from, those electrical potential signals (Ui), which correspond the actual band thickness deviations and which are emitted from the at least one feed end sensor (3).
20. A procedure in accord with claim 18 or 19, therein characterized, in that from the set band thickness and the measured actual band thickness in a case of simulation, the addition or the subtraction, that is to say, the addition or the removal of fiber band parts (=second draw frame machine) as well as the actual band thickness at the drawing of the actual number of fiber bands (=first draw frame machine) without simulation, the actual value of the A %-value is computed by a microprocessor (14; 14).
21. A procedure in accord with claim 20, therein characterized, in that the regulation intensity can be adjusted automatically or manually, up to the point that the real value of the A %-value (by measurements principally in the first and in the second draw frame machines) or the actual value of the A %-value or a mean value derived therefrom (by measuring in more than two draw frame machines) has reached a minimal value or understeps a predetermined value.
22. A procedure in accord with one of the claims 17 to 21, therein characterized, in that the at least second draw frame machine is a machine with a slower delivery speed as compared to the normal operation (=first draw frame machine) and in that the measured values of the actual band thickness for the at least second draw frame machine, by means of appropriate control of the regulation drive (11) can be so corrected, that the measured actual band thickness for the first and the second draw frame machines is essentially equal in size or the difference thereof lies below a predetermined threshold (“Adaption to Fiber Type”).
23. A procedure in accord with claim 22, therein characterized, in that the correction for various delivery speeds slower than the normal operation is carried out.
24. A procedure in accord with one of the claims 17 to 23, therein characterized, in that the comparison between the at least first and second draw frame machines, in the case of the change of a batch, is carried out at given intervals of time and/or upon the occurrence of predetermined happenings.
25. A procedure in accord with one of the claims 17 to 24, therein characterized, in that the optimized machine adaption as set forth in the foregoing claims permits an exchange of cans at the machine delivery end.

Priority Claims (1)

Number	Date	Country	Kind
102 14 649.7	Apr 2002	DE

Apparatus for the optimizing of the regulation adjustment of a spinning machine as well as a procedure corresponding thereto

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CPC

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Priority Claims (1)